The use of unmanned aerial drones to deliver an expanding range of products is becoming more and more efficient. Although there are some prior art devices which at ground level can be used as receptacles for delivered goods there has been no disclosures of extendable and retractable receptacle docking bays for use in multi-storey buildings or fixed above the ground on the vertical or near vertical elements of single-storey buildings. Delivery at ground level can be subject to theft or even damage or theft of the drone. Furthermore, building by laws seldom permit added structures which affect the aesthetics of a building. For example a prior art example of a drone landing pad as disclosed in WO 2015/103411 (Blacknight Holdings, LLC) would rarely be permitted in a multi-storey building as a plurality of the fixed shelves would significantly detract from the outward appearance of the building itself. In addition, the shelves would also provide platforms for cat burglars intent on climbing into high rise apartments and office blocks. Furthermore permanent fixed platforms would be a likely nesting place for birds and city vermin They would constitute a hazard in severe winds and promote ice formation over city streets. In some cases, it is not feasible to attach bracing for platforms to external cladding such as glass curtain wall buildings. It is therefore a general object of the present mention to seek to eliminate or ameliorate the disadvantages and limitations of the prior art. It is however a specific objective to provide an efficient and inventive retractable docking platform and parcel receptacle apparatus for delivery drones.